Increased cancer-specific mortality of very small size in carcinoembryonic antigen-elevated rectal cancer

Preoperative Carcinoembryonic Antigen as a Predictor of 5-Year Survival in Rectal Cancer: Proposing a New Prognostic Cutoff

PURPOSE

Carcinoembryonic antigen (CEA) is an important prognostic factor for rectal cancer. This study aims to introduce a novel cutoff point for CEA within the normal range to improve prognosis prediction and enhance patient stratification in rectal cancer patients.

METHODS

A total of 316 patients with stages I to III rectal cancer who underwent surgical tumor resection were enrolled. The Cox proportional hazards regression model was used to evaluate the impact of preoperative CEA level and other co-variates on overall survival (OS). The Youden Index method was used for CEA optimal cutoff estimation.

RESULTS

The mean follow-up period was 46.47 months. In risk-adjusted Cox proportional analysis, higher preoperative CEA levels (HR 1.17, CI 1.131.21; P < 0.001), and T-stage were associated with poor OS. The mean preoperative CEA level was significantly higher in patients with positive lymphovascular invasion (LVI) and perineural invasion (PNI) (CI: 1.06-2.45 and 0.75-2.33, respectively, P < 0.001, t test). Pathologic complete response (pCR) occurred in 71 (22.4%) cases. Patients with pCR had lower levels of preoperative CEA than non-pCR group (P = 0.002, CEApCR-CEAnonpCR =  - 1.3; t test). Using Youden Index, the estimated optimal CEA cutoff value for predicting OS was 2.8 ng/mL (sensitivity 90%; specificity 78.5%). Lower preoperative CEA levels predict higher pCR rates, aiding patient stratification and planning.

CONCLUSION

Preoperative CEA may play a role in the prediction of pCR in rectal cancer. Considering the CEA level of 2.8 ng/ml, as a newly defined cutoff point, patients with a worse prognosis can be identified prior to operation. PNI, along with LVI as independent predictors, may be contemplated as prognostic indicators to improve treatment strategies.

Prognostic Value of Tumor Size in Colon Cancer-Smaller is Better?

BACKGROUND

The prognostic value of tumor size in colon cancer remains controversial. This study aimed to reveal the correlation between tumor size and prognosis of colon cancer.

METHODS

A total of 491 patients with colon cancer were included in this study. The correlation of tumor size with prognosis, mismatch repair status, and other clinicopathological characteristics as well as tumor microenvironment was analyzed.

RESULTS

For stage IIA microsatellite stable (MSS) colon cancer, tumors sized <3.5 cm and ≥5 cm were associated with a poorer disease free survival (DFS) compared with tumors sized between 3.5 and 5 cm (P = .002). Small tumor size (HR = 5.098, P = .001) and large tumor size (HR = 2.749, P = .029) were found to be independent prognostic factors for stage IIA MSS colon cancer. Moreover, high expression of transgelin (TAGLN), a marker of cancer-associated fibroblasts (CAFs), was found to be an independent prognostic factor for poorer DFS (HR = 9.651, P = .009), which was also associated with smaller tumor size (P = .027).

CONCLUSION

Small (<3.5 cm) and large (≥5 cm) tumor sizes are associated with decreased DFS in stage IIA MSS colon cancer. Enrichment of TAGLN+ CAFs is associated with decreased DFS and small tumor size.

Tumor Deposits and Perineural Invasion had Comparable Impacts on the Survival of Patients With Non-metastatic Colorectal Adenocarcinoma: A Population-Based Propensity Score Matching and Competing Risk Analysis

BACKGROUND

Both tumor deposits (TD) and perineural invasion (PNI) have been identified as risk factors for poor survival in patients with non-metastatic colorectal adenocarcinoma (CRC). However, the adverse impacts of TD and PNI on the survival of patients with non-metastatic CRC have not been compared.

METHOD

Patients with non-metastatic CRC with known TD and PNI status were selected from the Surveillance, Epidemiology, and End Results (SEER) database. First, bivariate logistic regression analysis was utilized to identify the factors associated with TD and PNI status. Then, patients were divided into four groups, according to TD and PNI status. Propensity score matching (PSM) was performed to balance the baseline covariates. The impact of TD and PNI on survival was assessed by analyzing overall survival (OS) and cancer-specific mortality (CSM) rates. OS was calculated by the Kaplan-Meier method with log-rank analysis. CSM was estimated by competing risk analysis using the Fine and Gray model.

RESULTS

A total of 70 689 patients with CRC met the inclusion and exclusion criteria. The positive rates of TD and PNI were 9.37% and 9.91%, respectively. For TD, the most important risk factor was N stage. With respect to PNI, the most significant factor was T stage. Tumor location, tumor size, differentiation grade, and serum CEA level were also correlated with TD and PNI status. After PSM, 1849 pairs were selected. Patients with TD⁺PNI⁺ status had the worst 5 year CSM and 5 year OS. In addition, the long-term survival outcomes of patients with TD⁺PNI^- and TD^-PNI⁺ status were comparable.

CONCLUSION

The adverse impacts of TD and PNI on the survival of patients with non-metastatic CRC were comparable. CRC patients with both TD and PNI positive had the worst survival outcome.